/*
* Higher level upcall for a LAPB frame
*/
int ax25_process_rx_frame(ax25_cb *ax25, struct sk_buff *skb, int type, int dama)
{
int queued = 0, frametype, ns, nr, pf;
if (ax25->state == AX25_STATE_0)
return 0;
del_timer(&ax25->timer);
frametype = ax25_decode(ax25, skb, &ns, &nr, &pf);
switch (ax25->state) {
case AX25_STATE_1:
queued = ax25_state1_machine(ax25, skb, frametype, pf, type, dama);
break;
case AX25_STATE_2:
queued = ax25_state2_machine(ax25, skb, frametype, pf, type);
break;
case AX25_STATE_3:
queued = ax25_state3_machine(ax25, skb, frametype, ns, nr, pf, type, dama);
break;
case AX25_STATE_4:
queued = ax25_state4_machine(ax25, skb, frametype, ns, nr, pf, type, dama);
break;
}
ax25_set_timer(ax25);
return queued;
}
/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
* within the poll of any connected channel. Remember
* that we are not allowed to send anything unless we
* get polled by the Master.
*
* Thus we'll have to do parts of our T1 handling in
* ax25_enquiry_response().
*/
void ax25_t1_timeout(ax25_cb *ax25)
{
switch (ax25->state) {
case AX25_STATE_1:
if (ax25->n2count == ax25->n2) {
if (ax25->modulus == AX25_MODULUS) {
ax25_disconnect(ax25, ETIMEDOUT);
} else {
ax25->modulus = AX25_MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
ax25->n2count = 0;
ax25_send_control(ax25, AX25_SABM, ax25_dev_is_dama_slave(ax25->device) ? AX25_POLLOFF : AX25_POLLON, AX25_COMMAND);
}
} else {
ax25->n2count++;
if (ax25->modulus == AX25_MODULUS)
ax25_send_control(ax25, AX25_SABM, ax25_dev_is_dama_slave(ax25->device) ? AX25_POLLOFF : AX25_POLLON, AX25_COMMAND);
else
ax25_send_control(ax25, AX25_SABME, ax25_dev_is_dama_slave(ax25->device) ? AX25_POLLOFF : AX25_POLLON, AX25_COMMAND);
}
break;
case AX25_STATE_2:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_disconnect(ax25, ETIMEDOUT);
} else {
ax25->n2count++;
if (!ax25_dev_is_dama_slave(ax25->device))
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
}
break;
case AX25_STATE_3:
ax25->n2count = 1;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
ax25->state = AX25_STATE_4;
break;
case AX25_STATE_4:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
ax25_disconnect(ax25, ETIMEDOUT);
} else {
ax25->n2count++;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
}
break;
}
ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
ax25_set_timer(ax25);
}
/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
* within the poll of any connected channel. Remember
* that we are not allowed to send anything unless we
* get polled by the Master.
*
* Thus we'll have to do parts of our T1 handling in
* ax25_enquiry_response().
*/
void ax25_t1_timeout(ax25_cb * ax25)
{
switch (ax25->state) {
case AX25_STATE_1:
if (ax25->n2count == ax25->n2) {
if (ax25->modulus == MODULUS) {
#ifdef CONFIG_NETROM
nr_link_failed(&ax25->dest_addr, ax25->device);
#endif
ax25_clear_queues(ax25);
ax25->state = AX25_STATE_0;
if (ax25->sk != NULL) {
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = ETIMEDOUT;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
} else {
ax25->modulus = MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
ax25->n2count = 0;
ax25_send_control(ax25, SABM, ax25_dev_is_dama_slave(ax25->device)? POLLOFF : POLLON, C_COMMAND);
}
} else {
ax25->n2count++;
if (ax25->modulus == MODULUS) {
ax25_send_control(ax25, SABM, ax25_dev_is_dama_slave(ax25->device)? POLLOFF : POLLON, C_COMMAND);
} else {
ax25_send_control(ax25, SABME, ax25_dev_is_dama_slave(ax25->device)? POLLOFF : POLLON, C_COMMAND);
}
}
break;
case AX25_STATE_2:
if (ax25->n2count == ax25->n2) {
#ifdef CONFIG_NETROM
nr_link_failed(&ax25->dest_addr, ax25->device);
#endif
ax25_clear_queues(ax25);
ax25->state = AX25_STATE_0;
ax25_send_control(ax25, DISC, POLLON, C_COMMAND);
if (ax25->sk != NULL) {
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = ETIMEDOUT;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
} else {
ax25->n2count++;
if (!ax25_dev_is_dama_slave(ax25->device))
ax25_send_control(ax25, DISC, POLLON, C_COMMAND);
}
break;
case AX25_STATE_3:
ax25->n2count = 1;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
ax25->state = AX25_STATE_4;
break;
case AX25_STATE_4:
if (ax25->n2count == ax25->n2) {
#ifdef CONFIG_NETROM
nr_link_failed(&ax25->dest_addr, ax25->device);
#endif
ax25_clear_queues(ax25);
ax25_send_control(ax25, DM, POLLON, C_RESPONSE);
ax25->state = AX25_STATE_0;
if (ax25->sk != NULL) {
if (ax25->sk->debug)
printk("Link Failure\n");
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = ETIMEDOUT;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
} else {
ax25->n2count++;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
}
break;
}
ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
ax25_set_timer(ax25);
}
/*
* AX.25 TIMER
*
* This routine is called every 100ms. Decrement timer by this
* amount - if expired then process the event.
*/
static void ax25_timer(unsigned long param)
{
ax25_cb *ax25 = (ax25_cb *)param;
switch (ax25->state) {
case AX25_STATE_0:
/* Magic here: If we listen() and a new link dies before it
is accepted() it isn't 'dead' so doesn't get removed. */
if (ax25->sk == NULL || ax25->sk->destroy || (ax25->sk->state == TCP_LISTEN && ax25->sk->dead)) {
ax25_destroy_socket(ax25);
return;
}
break;
case AX25_STATE_3:
case AX25_STATE_4:
/*
* Check the state of the receive buffer.
*/
if (ax25->sk != NULL) {
if (ax25->sk->rmem_alloc < (ax25->sk->rcvbuf / 2) && (ax25->condition & AX25_COND_OWN_RX_BUSY)) {
ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
ax25->condition &= ~AX25_COND_ACK_PENDING;
if (!ax25->dama_slave)
ax25_send_control(ax25, AX25_RR, AX25_POLLOFF, AX25_RESPONSE);
break;
}
}
/*
* Check for frames to transmit.
*/
if (!ax25->dama_slave)
ax25_kick(ax25);
break;
default:
break;
}
if (ax25->t2timer > 0 && --ax25->t2timer == 0) {
if (ax25->state == AX25_STATE_3 || ax25->state == AX25_STATE_4) {
if (ax25->condition & AX25_COND_ACK_PENDING) {
ax25->condition &= ~AX25_COND_ACK_PENDING;
if (!ax25->dama_slave)
ax25_timeout_response(ax25);
}
}
}
if (ax25->t3timer > 0 && --ax25->t3timer == 0) {
/* dl1bke 960114: T3 expires and we are in DAMA mode: */
/* send a DISC and abort the connection */
if (ax25->dama_slave) {
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_disconnect(ax25, ETIMEDOUT);
ax25_set_timer(ax25);
return;
}
if (ax25->state == AX25_STATE_3) {
ax25->n2count = 0;
ax25_transmit_enquiry(ax25);
ax25->state = AX25_STATE_4;
}
ax25->t3timer = ax25->t3;
}
if (ax25->idletimer > 0 && --ax25->idletimer == 0) {
/* dl1bke 960228: close the connection when IDLE expires */
/* similar to DAMA T3 timeout but with */
/* a "clean" disconnect of the connection */
ax25_clear_queues(ax25);
ax25->n2count = 0;
if (!ax25->dama_slave) {
ax25->t3timer = 0;
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
} else {
ax25->t3timer = ax25->t3;
}
/* state 1 or 2 should not happen, but... */
if (ax25->state == AX25_STATE_1 || ax25->state == AX25_STATE_2)
ax25->state = AX25_STATE_0;
else
ax25->state = AX25_STATE_2;
ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
ax25->t2timer = 0;
if (ax25->sk != NULL) {
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = 0;
ax25->sk->shutdown |= SEND_SHUTDOWN;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
}
/* dl1bke 960114: DAMA T1 timeouts are handled in ax25_dama_slave_transmit */
/* nevertheless we have to re-enqueue the timer struct... */
if (ax25->t1timer == 0 || --ax25->t1timer > 0) {
ax25_set_timer(ax25);
return;
}
if (!ax25_dev_is_dama_slave(ax25->device)) {
if (ax25->dama_slave)
ax25->dama_slave = 0;
ax25_t1_timeout(ax25);
}
}
